1. Field of the Invention
The present invention relates to an intake manifold of an internal combustion engine, and more specifically, to a fuel vaporization accelerating apparatus for accelerating the vaporization of fuel.
2. Description of Prior Art
In case of conventional practice, a guide pipe was arranged in place in an intake manifold set at the lower end of a carburetor for the purpose of accelerating the vaporization of fuel, whereby mixed gas from the carburetor was led near to a riser. The said guide pipe was in the state of being suspended, with the flange section thereof set in place between the carburetor and a heat insulator fitted in place on the intake manifold. Therefore, the heat insulator was required to be subjected to machining or the like for the purpose of having the flange section set in place thereon in a proper manner. Furthermore, the mixed gas led through the guide pipe was soon subjected to diffusion all over in the intake manifold, and was not thoroughly vaporized or heated, either, by the riser. Hence the prior art structure was defective in terms of the state of distribution of the mixed gas to respective cylinders or in terms of the uniformity of the air-to-fuel ratio.